Rock drilling mechanism



Dec. 19, 1939. J. G. GRAHAM ROCK DRILLING MECHANISM Filed Aug. 6, 1936 ,2 Sheets-Sheet l dmam.

N MN5@ ww a# M. NN Q n .n N w @www a .MP A NN mv -M Mw' m lv (L AMK. .Q% QN NN NN Patented Dec. `19, 1939 ROCK DRILLING MEOHANISM James G. Graham, Butte, Mont., assignor to Sullivan Machinery Massachusetts .Companm a corporation of Application August 6, 1936, Serial No. 94,501l

3 Claims.

This invention relates to rock drilling mechanisms, and more particularly to improved feeding and guiding means for a hammer rock drill of the mounted type. e

An object of this invention is to provide an improved feeding and guiding means for a rock drill of the mounted type. Another object is to provide an improved pneumatically fed rock drill of the mounted type wherein, when the feeding mechanism is fully extended, the overall dimensions of the feeding mechanism are maintained at a minimum. Yet'another object is to provide an improved rock drill feeding mechanism whereby, with a relatively compact mechanism, a relatively long feeding travel for the drill is attained.

A further object is to provide an improved rockV drilling mechanism having improved feeding and guiding means whereby the rock drill is fed and guided in an improved manner. Astill further object of this invention is to provide an improved rock drill feeding mechanism of the multi-cylinder type wherein telescopically arranged cylinder elements are employed for effecting feeding of the drill. is to provide an improved pneumatic feeding means for a rock drill embodying parallel guide members along which the rock drill isslidably guided and having associated therewith telescopically arranged cylinder elements whereby, the

overall dimensions of the feeding mechanism are reduced to a minimum. Other'objects and advantages of the invention will, however, hereinafter more fully appear in the course of the following description and as more particularly pointed out in the appended claims. v

In the accompanying drawings, there is shown for purposes of illustration one form which the invention may assume in practice.

In these drawings:

Fig. 1 is a side elevational viewof the illustrative embodiment of the improved rock drill feeding andv guiding means.

Fig. 2 is an enlarged horizontal sectional view taken substantially on line 2--2 of Fig. l; showing the feeding mechanism in extended position.

Fig. 3 is an enlarged cross sectional viewtaken substantially on line 3-3 of Fig. 1.

Fig. 4 is a detail sectional view takenon 'line 4 4 of Fig. 3.

Fig. 5 is a detail sectional view taken on line 5-5 of Fig. 3.

Fig. 6 is an enlarged cross sectional view taken substantially on line 6-6 of Fig. 1.

Fig. '7 is an enlarged cross sectional `view taken substantially on line 1-1 of Fig. 1.

Still another object of this inventiony In this illustrative embodimentof the invention, the rock drill is generally designatedhi and the improved feeding and guiding means is generally designated 2. The drill guiding means comprises apair of tubular guiding members 3, 3 of elongated cylindrical form arranged in parallel. side by side relation and Vrigidly fixed together at their ends by transverse connecting portions il, l secured, as by welding, to the lower portions of the tubular guides 3, and intermediate 1 the ends of the guide members is atransverse frame 5 having an integral swivel plate or trun-` nion 5 adapted to be clamped in the saddle mountingy of a conventional rock drill support.

The rock drill I is of a conventional design comf prising a pressure fluid actuated hammer motor having a motor cylinder 'I containing a usual reciprocable hammer piston and provided with-a rear head block 8, a fronthead 9 and a front chuck housing Ill, the latter supporting, in a usual manner, a chuck for receiving the shank of a rock drill steel II. As the particular construction of the rock drill does not per se entery into this invention, illustration and description thereof are not considered necessary.

As illustrated, the forward endsl of the paraln lel tubular guides 3, 3 are closed by heads I2, I2, suitably threaded within the boresv of the guides, and these heads have an integral projection I3 on which is detachably mounted a guide or centraliZer i4 for-embracing the body ofthe drill steel I I to guide the latter during the drilling operation. The rock drill I, as illustrated herein, is supported directly onand between the parallel tubular guide members 3, 3 by the provision of a depending portion I5 which lmay be of suitable longitudinal'length so as to provide s uicient bearing surface,'and projecting between the guide members, while a cooperating guiding element ,It is removably secured to and spaced from the portion I5as-by screw bolts Il. -The velements l5 and I6 present arcuate bearingvsurfa'ces I8 `and IQ slidably engaging the adjacent sides of the outer peripheries of the tubular guide members 3, 3. It will thus be seen that the rock drill is entirely supported by and slidably yguidedfdiy rectly on the parallel guide members on the eX- terior peripheries of the `latter without the intermediation of any other guiding elements,

respect to the guide members, and each containing a reciprocable feed piston 2l. The piston rods 22'of the feed pistons 2| extend rearwardly through the packed rear heads 23 of the feed cylinders 2B and have respectively formed therein feed cylinders 24, 24 alined with the feed cylinders 26, 20 and containing reciprocable feed pistons 25, 25 respectively. The piston rods 25 of the feed pistons 25 extend rearwardly through the packed rear heads 2l of the feed cylinders 24, 24. As shown in Fig. 2, the rear ends of the parallel feed piston rods 26, 26 are rigidly connected together by a transverse connecting frame 28 extending therebetween and adapted to enter and move within longitudinal slots 29 formed along the inner sides of the tubular guide members, the slots 29 permitting movement of the transverse connecting frame 28 with respect to the tubular guide members as the feed pistons move forwardly. The rear head 8 of the rock drill is formed with a depending boss or lug 35, having a conical bore 3| in which is secured, as by a nut 32, the conical front end 33 of a connecting rod 34, the nut 32 being threaded, at 35, on this connecting rod and engagingl the rear surface of the rear head boss 30 in themanner shown in Fig. 2. This connecting rod extends rearwardly longitudinally in parallelism with and between the piston rods 26, 26 and is threadedly secured at its rear end at 36 within the transverse connecting frame 28 and is held therein by locknuts 31 threaded on the connecting rod and engagingthe forward surface on the connecting frame. It ywill thus be seen that, as the feed pistons are reciprocated within their respective cylinders with respect to the parallel guide members, the rock drill is fed along its guiding surfaces on the eXterior-peripheries of the parallel guide members 3, 3.

Now referring tothe means for supplying pressure fluid to the feeding cylinders and the rock drill, it will be noted thatV arranged in a transverse bore-46 formed in the rear head block 8 of the rock drill I is a rotary control valve 4| having an internal pressure chamber 42 to which pressure fluid is supplied through al pipe connection v43 from `any suitable source of supply. Arranged in a bore 44 parallel with the valve bore 40 is a rotary fed control valve 45. Herein mounted within the control valve 4| is a valve means 45 for regulating the feeding pressure. The rotary valves 4| and 45 and the regulating valve means 46 are generally similar to those described in Patent No. 2,015,678 granted October 1, 1935 to M. C. Huifman, and, as the specific structure of these valve means are clearly described in that patent, a description thereof herein is considered unnecessary, other than to state that the feeding pressure reducing valve 46 may be adjusted tov regulate the feeding pressure, and the feed control valve 45 may be operated to control the flow of feeding pressure to the feeding cylinders to effect reversal in the direction of feed irrespective of lthe feeding position of the control valve 4|; and

the control valve 4| may be operated to control the supply of pressure fluid to the hammer motor of the rock drill and to the feeding cylinders.

Pressure fluid is adapted to flow from the pressure chamber 42 in the control valve 4|, through `an axial passage 41 (see Fig. 3) under the control of the feeding pressure reducing valve 46, to a passage 48 in the valve 4| communicating with a circumferential groove 49 (see Fig. 4), the latter in turn communicating with a forward feed supply passage 50. A reverse feed supply passage 5| is communicable through a circumferential groove 52 on the valve 4| (see Fig. 5), in turn communicating through a passage 53 in the valve 4|, With the pressure ,chamber 42. The forward feed passage 5|! is communicable through passages in the control valve 45 with an annular groove 54 on the forward portion of the oonnecting rod 34, in turn communicating, through a passage 55 in the connecting rod 34, with a recess 56 in the connecting frame at the rear end of the connecting rod. This recess is connected by transverse passages 57, 57, in the connecting frame 28, with passages 59, 59 formed in the piston rods 25, 25 with the rear ends of the bores of the feed cylinders 24, 24 at the rear sides of Ithe pistons 25. The reverse feed passage 5| is communicable, through passages in the control valve 45, with an annular groove 65 on the forward portion of the connecting rod 34, in turn communicating, through a passage 6| in the connecting rod, with an annular groove 62 in the connecting frame 28 and surrounding the rearward portion of the connecting rod. The groove 62 is connected by passages 63, 63, formed in the connecting frame 28, with passages 64, 64 formed Within the piston rods 26, 26. These passages 64, 64 extend forwardly through the forward ends of the piston rods and communicate with the bores of the feed cylinders 24, 24 at the forward sides of the feed ypistons 25. The forward ends of the bores of the feed cylinders 24, 24 are connected through axial passages 65,765 in the forward heads of the feed cylinders 24, 24, While radial passages 66, 66 in thewalls of the piston rods 22, 22 connect the bores of the cylinders 24 with the bores of the cylinders 2|) at the rear sides of the feed pistons 2|. .The control valve 4| has a circumferential groove 5T (see Fig. 4), for connecting, through a passage 68, the passage 55, when the throttle valve" is turned into the position opposite from that shown in Fig. 4, with an exhaust passage 69,.while the reverse feed passage 5| is communicable through a circumferential groove 'l0 (see Fig. 5), on the control valve 4|, with an exhaust .passage 1|. The throttle valve, as `described in the above mentioned patent, has a passage for supplying pressure fluid from the pressure chamber 42 in the valve tothe supply passage of the hammer motor of the rock drill for operating the latter in the manner well understood4 by those skilled in the art.

The. mode of.v operation of the rock drilling mechanism .above described will be clearly apparent from the description given. When the valves are in the position shown in Figs. 4 and 5, pressure fluid may flow from the pressure chamber 42, in the control valve 4 through axial passage 47, past the feeding pressure regulating Valve 46 and through passage 43, groove LiL-forward feed passage 55, groove 54, passage 55 in the connecting rod, recess 56, passages 5l in the connecting frame and passages 5S in the piston rods 26 to the rear ends of the bores of the feed cylinders 24 at the rear sides of the feed pistons 25. At the same time, the opposite ends of the i pistons 25 overrun the ports 56 in the piston .rods 22, pressure fluid is also admitted from the bores of feed cylinders 24 to the rear ends of the bores of the feed cylinders 20 at the rear sides of the feed pistons 2l, the pressure in the bores of the feed cylinders '..li acting on the rear pressure areas of the feed pistons 2l to move `the latter forwardly relative tothe .feed cylinders 2l), 2li, the feed cylinders 2d and feed pistons 25 moving forwardly with the feed pistons 2i at that time. As a result, the rock drill l is fed forwardly along the guiding members 3, 3. When it is desired to effect reverse feed of the rock drill along its guideways relative to the parallel guide members, the throttle valve ll is turned into the position opposite from that shown in Figs. 4 and 5, so that the groove 52 connects the reverse feed passage 5l with the passage 53 communicating with the pressure chamber i2 in the control valve 4l, and the passage 68 is connected by the groove 5T with the .exhaust passage 59. vWhen the throttle valve is in this position, pressure fluid may flow from thepressurechamber 42,throughpassage 53, groove 52, reverse feed pasage 5l, groove Bil, passage Sl in the connecting rod 34, groove E2, passages 53 and passages ,F54 in the piston rods 25 to the forward ends of the bores of the feed cylinders 24 at the forward sides of the feed pistons 25.. Pressure fluid flows at this time from the bores of the feed cylinders 2li through the axial passages 55 to the bores of the feed cylinders 2d at the forward sides of the feed pistons 2l. Simultaneously, the rear ends of the bores ofthe feed cylinders 2li at the rear sides of the feed' pistons 25 are connected to exhaust through the passages 59 in the piston rods, passages 5l, recess 56, passage 55 in the connecting rods 3d, groove 5d., the passage 58, groove 5i on the control valve lill and exhaust passage t9. The pressure fluid flowing to the forward ends of the bores of feed cylinders acts on the forward pressure areas of the pistons 2l and 25 to move the latter rearwardly with respect to the guide members 3, 3, moving therewith the cylinders 2li, and, as a result, the rock drill l is fed rearwardly along the guiding surfaces of the tubular guiding members. It will oe evident that the forward feeding pressure may be regulated by the reducing valve 136, and the feeding pressure may be controlled at will and the feed reversedby the control valve 45 all in the manner described in the patent above referred to.

As a result of this invention, itwill be noted that an improved rock drilling mechanism is provided having a. novel feeding and guiding structure for the rock drill whereby the rock drill may be fed relative to the guiding means in an improved manner. It will further be noted that by the provision of the extremely compact arrangement of the feeding and guiding elements, it is possible, by the extremely compact structure, to obtain a relatively long range of drill feed. It will still further be noted that, by the particular double, telescopic feeding arrangement shown, it is possible to reduce the overall dimensions of the drilling mechanism when the feeding means is in its fully extended position, without reducing the feeding travel of the drill. Other uses and advantages of the improved rock drilling mechanism will be clearly apparent to those skilled in the art.

While there is in this aplication specifically described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illusmodified and embodied in various other :forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

l.` In a rock drilling mechanism, in combination, guiding means comprising a pair of tubular guideV members arranged in rigid parallel side by side relation, a rock drill guided o-n said guiding means for feeding movement longitudinally along said parallel guide members therebetween, and means for feeding said rock drill along said guid ing means comprising stationary feed cylinders arranged in said guide members respectively, feed pistons reciprocable in unison within said feed cylinders and having parallel tubular piston rods arranged within said guide members, said tubular piston rods having parallel feed cylinders formed therein, feed pistons reciprocable in unison within said last mentioned feed cylinders and having parallel piston rods projecting outwardly from said guide members, a connecting rod parallel with said last mentioned piston rods and ar-1 ranged longitudinally between said guide members, said connecting rod secured to the rock drill,

and a transverse connection between the outer ends of said last mentioned piston rods and said connecting rod, said guide members slotted longitudinally along the adjacent inner sides thereof to receive said transverse connection, said slots permitting longitudinal movement of said transverse connection relative to said guide members as the rock drill is fed along said guiding means.

2. In a rock drilling mechanism, in combination, guiding means comprising a tubular guide cylinder having on its exterior periphery an arcuate drill guiding surface, a rock drill movable longitudinally along said guiding means and having an arcuate bearing surface slidably guided on said peripheral guiding surface of said guide cylinder, and means for feeding the rock drill longitudinally along said guiding means com` prising a feed cylinder formed within a portion of said guide cylinder, a feed piston reciprocable in said feed cylinder and having a tubular piston rod arranged within said guide cylinder, said piston rod having a feed cylinder formed therein, a feed piston reciprocable in said last mentioned feed. cylinder and having a pistonrod, a connecting rod extending longitudinally along one side of said guide cylinder in parallelism with said last mentioned piston rod and secured to the rock drill, yand a transverse connection between the outer ends of said last mentioned piston rod and said connecting rod, said guide cylinder being longitudinally slotted through a wall thereof to receive said transverse connection, said slot permitting longitudinal movement of said transverse connection relative to said guide cylinder as the Lrock drill moves longitudinally along the guiding means.

3. In a rock drilling mechanism, in combination, guiding means comprising a pair of tubular guide cylinders arranged in rigid parallel side by side relation and having on their exterior peripheries arcuate drill guiding surfaces, a rock drill movable longitudinally along said guiding means ciprocable in unison Within said feed cylinders and having parallel tubular piston rods arranged within said guide cylinders, said piston rods having parallel feed cylinders formed therein, feed pistons reciprocable in unison Within said last mentioned feed cylinders and having parallel piston rods, a connecting rod arranged longitudinally between said guide cylinders in parallelism With said last mentioned piston rods and secured l0 to the rock drill, and a transverse connection between the outer ends of said last mentioned piston rods and said connecting rod, the inner adjacent sides of said guide cylinders being longitudinally slotted through the Walls thereof to receive said transverse connection, said slots permitting longitudinal movement of said transverse connection relative to said guide cylinders as the rock drill moves longitudinally along said guiding means,

JAMES G. GRAHAM. 

